Spatial predictors of immunotherapy response in triple-negative breast cancer.

Immune checkpoint blockade (ICB) benefits some patients with triple-negative breast cancer, but what distinguishes responders from non-responders is unclear1. Because ICB targets cell-cell interactions2, we investigated the impact of multicellular spatial organization on response, and explored how ICB remodels the tumour microenvironment. We show that cell phenotype, activation state and spatial location are intimately linked, influence ICB effect and differ in sensitive versus resistant tumours early on-treatment. We used imaging mass cytometry3 to profile the in situ expression of 43 proteins in tumours from patients in a randomized trial of neoadjuvant ICB, sampled at three timepoints (baseline, n = 243; early on-treatment, n = 207; post-treatment, n = 210). Multivariate modelling showed that the fractions of proliferating CD8+TCF1+T cells and MHCII+ cancer cells were dominant predictors of response, followed by cancer-immune interactions with B cells and granzyme B+ T cells. On-treatment, responsive tumours contained abundant granzyme B+ T cells, whereas resistant tumours were characterized by CD15+ cancer cells. Response was best predicted by combining tissue features before and on-treatment, pointing to a role for early biopsies in guiding adaptive therapy. Our findings show that multicellular spatial organization is a major determinant of ICB effect and suggest that its systematic enumeration in situ could help realize precision immuno-oncology.

Sacituzumab Govitecan in Metastatic Triple-Negative Breast Cancer.

BACKGROUND: Patients with metastatic triple-negative breast cancer have a poor prognosis. Sacituzumab govitecan is an antibody-drug conjugate composed of an antibody targeting the human trophoblast cell-surface antigen 2 (Trop-2), which is expressed in the majority of breast cancers, coupled to SN-38 (topoisomerase I inhibitor) through a proprietary hydrolyzable linker. METHODS: In this randomized, phase 3 trial, we evaluated sacituzumab govitecan as compared with single-agent chemotherapy of the physician's choice (eribulin, vinorelbine, capecitabine, or gemcitabine) in patients with relapsed or refractory metastatic triple-negative breast cancer. The primary end point was progression-free survival (as determined by blinded independent central review) among patients without brain metastases. RESULTS: A total of 468 patients without brain metastases were randomly assigned to receive sacituzumab govitecan (235 patients) or chemotherapy (233 patients). The median age was 54 years; all the patients had previous use of taxanes. The median progression-free survival was 5.6 months (95% confidence interval [CI], 4.3 to 6.3; 166 events) with sacituzumab govitecan and 1.7 months (95% CI, 1.5 to 2.6; 150 events) with chemotherapy (hazard ratio for disease progression or death, 0.41; 95% CI, 0.32 to 0.52; P<0.001). The median overall survival was 12.1 months (95% CI, 10.7 to 14.0) with sacituzumab govitecan and 6.7 months (95% CI, 5.8 to 7.7) with chemotherapy (hazard ratio for death, 0.48; 95% CI, 0.38 to 0.59; P<0.001). The percentage of patients with an objective response was 35% with sacituzumab govitecan and 5% with chemotherapy. The incidences of key treatment-related adverse events of grade 3 or higher were neutropenia (51% with sacituzumab govitecan and 33% with chemotherapy), leukopenia (10% and 5%), diarrhea (10% and <1%), anemia (8% and 5%), and febrile neutropenia (6% and 2%). There were three deaths owing to adverse events in each group; no deaths were considered to be related to sacituzumab govitecan treatment. CONCLUSIONS: Progression-free and overall survival were significantly longer with sacituzumab govitecan than with single-agent chemotherapy among patients with metastatic triple-negative breast cancer. Myelosuppression and diarrhea were more frequent with sacituzumab govitecan. (Funded by Immunomedics; ASCENT ClinicalTrials.gov number, NCT02574455; EudraCT number, 2017-003019-21.).

Breast cancers with high proliferation and low ER-related signalling have poor prognosis and unique molecular features with implications for therapy.

BACKGROUND: Luminal breast cancers with high proliferation (MKShi) and low ER-related signalling (ERSlo) have a poor prognosis. We investigated treatment responses and molecular features of MKShi/ERSlo tumours to inform potential therapies. METHODS: Gene expression data from patients who received neoadjuvant chemotherapy (NAC) without (MDACC, N = 199) or with pembrolizumab (I-SPY2, N = 40), or endocrine therapy (NET) without (POETIC, N = 172) or with palbociclib (NeoPalAna, N = 32) were analyzed to assess treatment response by MKS/ERS-subgroups. TCGA was used to assess the mutational landscape and biomarkers associated with palbociclib-resistance (Cyclin-E, RBsig, IRPR) and immunotherapy-response (TMB, TILs, T-cell inflamed) by MKS/ERS-subgroups. RESULTS: Compared to MKShi/ERShi tumours, MKShi/ERSlo tumours had higher pathological response rates to NAC (22% vs 8%, p = 0.06) but a higher recurrence risk (4-year metastasis-free survival 70% vs 94%, p = 0.01). MKShi/ERSlo tumours frequently harboured TP53 (34%) and PIK3CA (33%) mutations, and showed high expression of Cyclin-E, RBsig and IRPR, high TMB and elevated TIL and T-cell inflamed metagene expression. MKShi/ERSlo tumours retained high proliferation after NET with or without palbociclib but had higher pathological complete response rates when pembrolizumab was added to NAC (42% vs 21%, p = 0.07). CONCLUSIONS: MKShi/ERSlo tumours have dismal outcomes and are enriched in chemotherapy-sensitive but ET- and palbociclib-resistant tumours. Biomarker analysis and clinical data suggest a potential role for immunotherapy in this group.

Neoadjuvant treatment with trastuzumab and pertuzumab plus palbociclib and fulvestrant in HER2-positive, ER-positive breast cancer (NA-PHER2): an exploratory, open-label, phase 2 study.

BACKGROUND: In the neoadjuvant setting, blockade of HER2 plus use of an aromatase inhibitor in patients with HER2-positive and oestrogen receptor (ER)-positive breast cancer leads to a pathological complete response in 21% of patients. Convergence of HER2 and ER signals on RB1 suggests that a combined pharmacological intervention directed to these targets could be synergistic. To test this approach, we combined palbociclib to block RB1, fulvestrant to block ER, and trastuzumab with pertuzumab to block HER2 in patients with HER2-positive, ER-positive breast cancer. METHODS: NA-PHER2 is a multicohort, open-label, exploratory, phase 2 study done at seven sites in Italy. Patients were eligible for the first cohort if they had previously untreated, histologically confirmed, unilateral, invasive, HER2-positive, ER-positive breast cancer and were suitable for neoadjuvant therapy. Patients were treated every 3 weeks with intravenous trastuzumab (8 mg/kg loading dose followed by 6 mg/kg) and intravenous pertuzumab (840 mg loading dose in the first cycle and then at 420 mg) for six cycles plus oral palbociclib (125 mg once a day for 21 days in a 4-week cycle) and intramuscular fulvestrant (500 mg) every 4 weeks for five cycles. The coprimary endpoints were change from baseline in Ki67 expression at 2 weeks of treatment and at surgery (16 weeks after treatment) and changes in apoptosis from baseline to surgery. Secondary endpoints were clinical objective response (according to modified Response Evaluation Criteria in Solid Tumors) and pathological complete response. All patients who met eligibility criteria were assessed for the primary and secondary endpoints. All patients who received at least one cycle of therapy were assessed for safety. This trial is registered with ClinicalTrials.gov, number NCT02530424. The trial is ongoing and two further cohorts are being enrolled. FINDINGS: Between May 20, 2015, and Feb 8, 2016, we enrolled 36 patients, of whom one was deemed ineligible for the study and five were found to be HER2-negative on retrospective analysis. Thus, 35 patients were included in safety analyses and 30 were assessed for the primary and secondary endpoints. At baseline, geometric mean Ki67 expression was 31·9 (SD 15·7), versus 4·3 (15·0) at week 2 (n=25; p<0·0001) and 12·1 (20·0) at time of surgery (n=22; p=0·013). The geometric mean for apoptosis was 1·2 (SD 0·3) at baseline versus 0·4 (0·4; p=0·019) at surgery. A clinical objective response immediately before surgery was achieved by 29 (97%; 95% CI 83-100) of 30 patients. At surgery, eight (27%; 95% CI 12-46) patients had a pathological complete response in breast and axillary nodes. The most frequent grade 3 adverse events were neutropenia (ten [29%]), diarrhoea (five [14%]), and stomatitis, increased alanine aminotransferase, and hypersensitivity reactions (one [3%] of each event). No grade 4 or serious adverse events were recorded in the study and there were no deaths. INTERPRETATION: The combination of palbociclib, fulvestrant, trastuzumab, and pertuzumab had a significant effect on the expression of Ki67 at 2 weeks and at surgery. Triple targeting of ER, HER2, and RB1 in HER2-positive and ER-positive breast cancer could be an effective chemotherapy-free treatment strategy. Further clinical testing and additional molecular characterisation is necessary, not only in hormone receptor-positive tumours but also in tumours without HER2 amplification. FUNDING: Pfizer and Roche.

Strategies for clinical development of monoclonal antibodies beyond first-in-human trials: tested doses and rationale for dose selection.

BACKGROUND: Our previous survey on first-in-human trials (FIHT) of monoclonal antibodies (mAbs) showed that, due to their limited toxicity, the recommended phase II dose (RP2D) was only tentatively defined. METHODS: We identified, by MEDLINE search, articles on single-agent trials of mAbs with an FIHT included in our previous survey. For each mAb, we examined tested dose(s) and dose selection rationale in non-FIHTs (NFIHTs). We also assessed the correlation between doses tested in the registration trials (RTs) of all FDA-approved mAbs and the corresponding FIHT results. RESULTS: In the 37 dose-escalation NFIHTs, the RP2D indication was still poorly defined. In phase II-III NFIHTs (n=103 on 37 mAbs), the FIHT RP2D was the only dose tested for five mAbs. For 16 mAbs, only doses different from the FIHT RP2D or the maximum administered dose (MAD) were tested and the dose selection rationale infrequently indicated. In the 60 RTs on 27 FDA-approved mAbs with available FIHT, the FIHT RP2D was tested only for two mAbs, and RT doses were much lower than the FIHT MAD. CONCLUSIONS: The rationale beyond dose selection in phase II and III trials of mAbs is often unclear in published articles and not based on FIHT data.

HER2-positive breast cancer.

Anti-HER2 treatment for HER2-positive breast cancer has changed the natural biology of this disease. This Series article reviews the main achievements so far in the treatment of both metastatic and early HER2-positive breast cancer. The success of neoadjuvant therapy in HER2-positive early breast cancer is especially acknowledged, as pertuzumab has been approved on the basis of a higher proportion of patients achieving a pathological complete response with pertuzumab and trastuzumab than with trastuzumab alone in a neoadjuvant study. Event-free survival after the confirmatory adjuvant trial completed recruitment was numerically better with pertuzumab plus trastuzumab than with trastuzumab alone. With survival rates of almost 5 years in women with metastatic HER2-positive breast cancer and 75% of patients achieving a pathological complete response, new treatments in the past decade have clearly improved the prognosis of HER2-positive breast cancer. Despite these achievements, however, the persisting high toll of deaths resulting from HER2-positive breast cancer calls for continued, intensive clinical research of newer therapies and combinations.

11 years' follow-up of trastuzumab after adjuvant chemotherapy in HER2-positive early breast cancer: final analysis of the HERceptin Adjuvant (HERA) trial.

BACKGROUND: Clinical trials have shown that trastuzumab, a recombinant monoclonal antibody against HER2 receptor, significantly improves overall survival and disease-free survival in women with HER2-positive early breast cancer, but long-term follow-up data are needed. We report the results of comparing observation with two durations of trastuzumab treatment at a median follow-up of 11 years, for patients enrolled in the HERA (HERceptin Adjuvant) trial. METHODS: HERA (BIG 1-01) is an international, multicentre, open-label, phase 3 randomised trial of 5102 women with HER2-positive early breast cancer, who were enrolled from hospitals in 39 countries between Dec 7, 2001, and June 20, 2005. After completion of all primary therapy (including, surgery, chemotherapy, and radiotherapy as indicated), patients were randomly assigned (1:1:1) to receive trastuzumab for 1 year (once at 8 mg/kg of bodyweight intravenously, then 6 mg/kg once every 3 weeks) or for 2 years (with the same dose schedule), or to the observation group. Primary endpoint is disease-free survival, and analyses are in the intention-to-treat population. Hazard ratios (HRs) were estimated from Cox models, and survival curves were estimated by the Kaplan-Meier method. Comparison of 2 years versus 1 year of trastuzumab is based on 366-day landmark analyses. This study is registered with ClinicalTrials.gov (NCT00045032). FINDINGS: Of the 5102 women randomly assigned in the HERA trial, three patients had no evidence of having provided written informed consent to participate. We followed up the intention-to-treat population of 5099 patients (1697 in observation, 1702 in 1-year trastuzumab, and 1700 in 2-years trastuzumab groups). After a median follow-up of 11 years (IQR 10·09-11·53), random assignment to 1 year of trastuzumab significantly reduced the risk of a disease-free survival event (HR 0·76, 95% CI 0·68-0·86) and death (0·74, 0·64-0·86) compared with observation. 2 years of adjuvant trastuzumab did not improve disease free-survival outcomes compared with 1 year of this drug (HR 1·02, 95% CI 0·89-1·17). Estimates of 10-year disease-free survival were 63% for observation, 69% for 1 year of trastuzumab, and 69% for 2 years of trastuzumab. 884 (52%) patients assigned to the observation group selectively crossed over to receive trastuzumab. Cardiac toxicity remained low in all groups and occurred mostly during the treatment phase. The incidence of secondary cardiac endpoints was 122 (7·3%) in the 2-years trastuzumab group, 74 (4·4%) in the 1-year trastuzumab group, and 15 (0·9%) in the observation group. INTERPRETATION: 1 year of adjuvant trastuzumab after chemotherapy for patients with HER2-positive early breast cancer significantly improves long-term disease-free survival, compared with observation. 2 years of trastuzumab had no additional benefit. FUNDING: F Hoffmann-La Roche (Roche).

Trastuzumab emtansine versus capecitabine plus lapatinib in patients with previously treated HER2-positive advanced breast cancer (EMILIA): a descriptive analysis of final overall survival results from a randomised, open-label, phase 3 trial.

BACKGROUND: The antibody-drug conjugate trastuzumab emtansine is indicated for the treatment of patients with HER2-positive metastatic breast cancer previously treated with trastuzumab and a taxane. Approval of this drug was based on progression-free survival and interim overall survival data from the phase 3 EMILIA study. In this report, we present a descriptive analysis of the final overall survival data from that trial. METHODS: EMILIA was a randomised, international, open-label, phase 3 study of men and women aged 18 years or older with HER2-positive unresectable, locally advanced or metastatic breast cancer previously treated with trastuzumab and a taxane. Enrolled patients were randomly assigned (1:1) via a hierarchical, dynamic randomisation scheme and an interactive voice response system to trastuzumab emtansine (3·6 mg/kg intravenously every 3 weeks) or control (capecitabine 1000 mg/m2 self-administered orally twice daily on days 1-14 on each 21-day cycle, plus lapatinib 1250 mg orally once daily on days 1-21). Randomisation was stratified by world region (USA vs western Europe vs or other), number of previous chemotherapy regimens for unresectable, locally advanced, or metastatic disease (0 or 1 vs >1), and disease involvement (visceral vs non-visceral). The coprimary efficacy endpoints were progression-free survival (per independent review committee assessment) and overall survival. Efficacy was analysed in the intention-to-treat population; safety was analysed in all patients who received at least one dose of study treatment, with patients analysed according to the treatment actually received. On May 30, 2012, the study protocol was amended to allow crossover from control to trastuzumab emtansine after the second interim overall survival analysis crossed the prespecified overall survival efficacy boundary. This study is registered with ClinicalTrials.gov, number NCT00829166. FINDINGS: Between Feb 23, 2009, and Oct 13, 2011, 991 eligible patients were enrolled and randomly assigned to either trastuzumab emtansine (n=495) or capecitabine and lapatinib (control; n=496). In this final descriptive analysis, median overall survival was longer with trastuzumab emtansine than with control (29·9 months [95% CI 26·3-34·1] vs 25·9 months [95% CI 22·7-28·3]; hazard ratio 0·75 [95% CI 0·64-0·88]). 136 (27%) of 496 patients crossed over from control to trastuzumab emtansine after the second interim overall survival analysis (median follow-up duration 24·1 months [IQR 19·5-26·1]). Of those patients originally randomly assigned to trastuzumab emtansine, 254 (51%) of 495 received capecitabine and 241 [49%] of 495 received lapatinib (separately or in combination) after study drug discontinuation. In the safety population (488 patients treated with capecitabine plus lapatinib, 490 patients treated with trastuzumab emtansine), fewer grade 3 or worse adverse events occurred with trastuzumab emtansine (233 [48%] of 490) than with capecitabine plus lapatinib control treatment (291 [60%] of 488). In the control group, the most frequently reported grade 3 or worse adverse events were diarrhoea (103 [21%] of 488 patients) followed by palmar-plantar erythrodysaesthesia syndrome (87 [18%]), and vomiting (24 [5%]). The safety profile of trastuzumab emtansine was similar to that reported previously; the most frequently reported grade 3 or worse adverse events in the trastuzumab emtansine group were thrombocytopenia (70 [14%] of 490), increased aspartate aminotransferase levels (22 [5%]), and anaemia (19 [4%]). Nine patients died from adverse events; five of these deaths were judged to be related to treatment (two in the control group [coronary artery disease and multiorgan failure] and three in the trastuzumab emtansine group [metabolic encephalopathy, neutropenic sepsis, and acute myeloid leukaemia]). INTERPRETATION: This descriptive analysis of final overall survival in the EMILIA trial shows that trastuzumab emtansine improved overall survival in patients with previously treated HER2-positive metastatic breast cancer even in the presence of crossover treatment. The safety profile was similar to that reported in previous analyses, reaffirming trastuzumab emtansine as an efficacious and tolerable treatment in this patient population. FUNDING: F Hoffmann-La Roche/Genentech.

Biomarker analysis of the NeoSphere study: pertuzumab, trastuzumab, and docetaxel versus trastuzumab plus docetaxel, pertuzumab plus trastuzumab, or pertuzumab plus docetaxel for the neoadjuvant treatment of HER2-positive breast cancer.

BACKGROUND: NeoSphere showed significantly higher pathologic complete response (pCR) with neoadjuvant pertuzumab, trastuzumab, and docetaxel compared with trastuzumab plus docetaxel, pertuzumab plus trastuzumab, or pertuzumab plus docetaxel. We assessed associations between human epidermal growth factor receptor 2 (HER2) pathway-related biomarkers and clinical outcome in response to these regimens. METHODS: Tumor, serum, and whole blood samples were collected at baseline and post neoadjuvant treatment before surgery. Associations between biomarkers and pCR, and between biomarkers and clinical variables were assessed in the overall and estrogen receptor (ER)-positive and ER-negative populations. Changes in serum marker levels between baseline and post-neoadjuvant treatment were examined. RESULTS: No markers were associated with pCR across all groups; however, significant associations were observed for two markers in individual groups. High HER2 was significantly associated with higher pCR rates (P = 0.001) and a significant treatment interaction (P = 0.0236) with pertuzumab, trastuzumab, and docetaxel (odds ratio 2.07, P = 0.01). Low serum transforming growth factor alpha (TGFα) was associated with higher pCR rates with pertuzumab plus trastuzumab (P = 0.04) without a significant treatment interaction. Presence of truncated HER2 did not affect pCR. A non-significant decreased pCR benefit was observed consistently across groups in patients with mutated PIK3CA while the treatment benefit from pertuzumab was maintained when comparing the trastuzumab plus docetaxel and pertuzumab, trastuzumab, and docetaxel groups. Notably, PIK3CA exon 9 mutations were associated with residual disease (pooled groups), which was not found for exon 20 mutations. Serum HER2 extracellular domain levels were significantly increased between baseline and post-neoadjuvant treatment in the non-trastuzumab-treated group, and decreased in the trastuzumab-containing groups (likely due to trastuzumab's mechanism of action). Differences in biomarker profiles according to ER status were observed. CONCLUSIONS: The observed associations of HER2 protein levels with sensitivity to pertuzumab, and of PIK3CA exon 9 mutation to lack of sensitivity to HER2-targeted monoclonal antibody treatment, warrant further investigation. Previously reported findings of truncated forms of HER2 as resistance markers to HER2-targeted treatment could not be confirmed in NeoSphere. Conventional HER2 assessment should continue and HER2 remains the only biomarker suitable for patient selection in this population. TRIAL REGISTRATION: Clinicaltrials.gov, NCT00545688 . Registered on 16 October 2007.

5-year analysis of neoadjuvant pertuzumab and trastuzumab in patients with locally advanced, inflammatory, or early-stage HER2-positive breast cancer (NeoSphere): a multicentre, open-label, phase 2 randomised trial.

BACKGROUND: In the primary analysis of the NeoSphere trial, patients given neoadjuvant pertuzumab, trastuzumab, and docetaxel showed a significantly improved pathological complete response compared with those given trastuzumab and docetaxel after surgery. Here, we report 5-year progression-free survival, disease-free survival, and safety. METHODS: In this multicentre, open-label, phase 2 randomised trial in hospitals and medical clinics, treatment-naive adults with locally advanced, inflammatory, or early-stage HER2-positive breast cancer were randomly assigned (1:1:1:1) to receive four neoadjuvant cycles of trastuzumab (8 mg/kg loading dose, followed by 6 mg/kg every 3 weeks) plus docetaxel (75 mg/m(2) every 3 weeks, increasing to 100 mg/m(2) from cycle 2 if tolerated; group A), pertuzumab (840 mg loading dose, followed by 420 mg every 3 weeks) and trastuzumab plus docetaxel (group B), pertuzumab and trastuzumab (group C), or pertuzumab and docetaxel (group D). After surgery, patients received three cycles of FEC (fluorouracil 600 mg/m(2), epirubicin 90 mg/m(2), and cyclophosphamide 600 mg/m(2)) every 3 weeks (patients in group C received four cycles of docetaxel prior to FEC), and trastuzumab 6 mg/kg every 3 weeks to complete 1 year's treatment (17 cycles in total). Randomisation was done by a central centre using dynamic allocation, stratified by operable, locally advanced, and inflammatory breast cancer, and by oestrogen and/or progesterone receptor positivity. Safety analyses were done according to treatment received. The primary endpoint (pathological complete response) was previously reported; secondary endpoints reported here are 5-year progression-free survival (analysed in the intention-to-treat population) and disease-free survival (analysed in patients who had surgery). Secondary and exploratory analyses were not powered for formal statistical hypothesis testing, and therefore results are for descriptive purposes only. The study ended on Sept 22, 2014 (last patient, last visit). This study is registered with ClinicalTrials.gov, number NCT00545688. FINDINGS: Between Dec 17, 2007, and Dec 22, 2009, 417 eligible patients were randomly assigned to group A (107 patients), group B (107 patients), group C (107 patients), or group D (96 patients). One patient in group A withdrew before treatment. One patient assigned to group D received group A treatment, one patient assigned to group D received group B treatment, and one patient assigned to group B received group C treatment. At clinical cutoff, 87 patients had progressed or died. 5-year progression-free survival rates were 81% (95% CI 71-87) for group A, 86% (77-91) for group B, 73% (64-81) for group C, and 73% (63-81) for group D (hazard ratios 0·69 [95% CI 0·34-1·40] group B vs group A, 1·25 [0·68-2·30] group C vs group A, and 2·05 [1·07-3·93] group D vs group B). Disease-free survival results were consistent with progression-free survival results and were 81% (95% CI 72-88) for group A, 84% (72-91) for group B, 80% (70-86) for group C, and 75% (64-83) for group D. Patients who achieved total pathological complete response (all groups combined) had longer progression-free survival compared with patients who did not (85% [76-91] in patients who achieved total pathological response vs 76% [71-81] in patients who did not achieve total pathological response; hazard ratio 0·54 [95% CI 0·29-1·00]). There were no new or long-term safety concerns and tolerability was similar across groups (neoadjuvant and adjuvant treatment periods combined). The most common grade 3 or worse adverse events were neutropenia (group A: 71 [66%] of 107 patients; group B: 59 [55%] of 107; group C: 40 [37%] of 108; group D: 60 [64%] of 94), febrile neutropenia (group A: 10 [9%]; group B: 12 [11%]; group C: 5 [5%]; group D: 15 [16%]), and leucopenia (group A: 13 [12%]; group B: 6 [6%]; group C: 4 [4%]; group D: 8 [9%]). The number of patients with one or more serious adverse event was similar across groups (19-22 serious adverse events per group in 18-22% of patients). INTERPRETATION: Progression-free survival and disease-free survival at 5-year follow-up show large and overlapping CIs, but support the primary endpoint (pathological complete response) and suggest that neoadjuvant pertuzumab is beneficial when combined with trastuzumab and docetaxel. Additionally, they suggest that total pathological complete response could be an early indicator of long-term outcome in early-stage HER2-positive breast cancer. FUNDING: F Hoffmann-La Roche.

Phase 1B trial of Nab-paclitaxel plus gemcitabine, capecitabine, and cisplatin (PAXG regimen) in patients with unresectable or borderline resectable pancreatic adenocarcinoma.

BACKGROUND: Nab-paclitaxel-gemcitabine combination significantly improved overall survival over gemcitabine in metastatic pancreatic adenocarcinoma. A phase 1b trial was performed (ClinicalTrials.gov number, NCT01730222) to determine the recommended phase 2 dose (RP2D) of nab-paclitaxel in combination with cisplatin, capecitabine, and gemcitabine at fixed dose (800, 30, and 1250 mg m(-2) every 2 weeks, respectively; PAXG regimen). METHODS: Nab-paclitaxel doses were escalated from 100 (level one) to 125 (level two) and 150 mg m(-2) (level three) every 2 weeks in cohorts of 3-6 patients with pathologically confirmed unresectable or borderline resectable pancreatic adenocarcinoma. RESULTS: Between Dec 2012 and Apr 2014, 24 patients were enroled (3 at level one, 5 at level two, 16 at level three) and received 117 cycles of PAXG. No dose-limiting toxicity occurred and level three was the RP2D. At this dose, nab-paclitaxel dose-intensity was 91%. Worse per patient grade 3/4 toxicity were neutropenia 25/31%; fatigue 19%; anaemia and hand-foot syndrome 12%, nausea 6%, and febrile neutropenia 6%. A partial response (PR) was observed in 16 (67%) and stable disease (SD) in 8 patients (33%). Among 21 patients with a baseline positive positron emission tomography (PET) scan, a complete metabolic response was observed in 9 (43%), PR in 10 (48%), SD in 2. CA19-9 decreased by ⩾49% in all the 19 patients with elevated basal value. Six patients were resected after chemotherapy. Progression-free survival at 6 months (PFS-6) was 96%. CONCLUSIONS: The RP2D of nab-paclitaxel in the PAXG regimen was 150 mg m(-2) every 2 weeks. The preliminary results are promising and warrant further exploration.

Trastuzumab re-treatment following adjuvant trastuzumab and the importance of distant disease-free interval: the HERA trial experience.

This retrospective analysis conducted using data from patients enrolled onto the Herceptin Adjuvant has two objectives: The first is to evaluate the impact of the time interval between the end of adjuvant trastuzumab and distant recurrence (TDRI) upon overall survival (OS). The second is to describe the duration of trastuzumab-based regimens in the metastatic setting for patients previously treated with adjuvant trastuzumab. The first objective included 187 patients treated with adjuvant trastuzumab and diagnosed with distant recurrence at 4-year median follow-up. The second objective included data from questionnaires sent to investigators retreating patients with trastuzumab upon distant recurrence: 144 of 156 questionnaires were returned (93 %), and 90 patients were selected based on available clinical information and consent for subsequent studies. There was no statistically significant relationship between TDRI following 1 year of adjuvant trastuzumab and OS from distant recurrence: hazard ratio 0.991, p = 0.46. The median OS from distant recurrence was numerically longer among patients with a TDRI of ≥12 months (n = 103) than <12 months (n = 84) but not statistically significant (23.7 vs. 17.8 months, p = 0.47). The median duration of first-line trastuzumab-based regimens for patients previously treated with adjuvant trastuzumab and diagnosed with distant disease recurrence was 8.8 months (n = 88). This retrospective, exploratory study suggests that TDRI did not impact on OS measured from distant recurrence. We argue that prospective collection of treatment information beyond disease progression should be included in future clinical studies.

Pathological complete response and long-term clinical benefit in breast cancer: the CTNeoBC pooled analysis.

BACKGROUND: Pathological complete response has been proposed as a surrogate endpoint for prediction of long-term clinical benefit, such as disease-free survival, event-free survival (EFS), and overall survival (OS). We had four key objectives: to establish the association between pathological complete response and EFS and OS, to establish the definition of pathological complete response that correlates best with long-term outcome, to identify the breast cancer subtypes in which pathological complete response is best correlated with long-term outcome, and to assess whether an increase in frequency of pathological complete response between treatment groups predicts improved EFS and OS. METHODS: We searched PubMed, Embase, and Medline for clinical trials of neoadjuvant treatment of breast cancer. To be eligible, studies had to meet three inclusion criteria: include at least 200 patients with primary breast cancer treated with preoperative chemotherapy followed by surgery; have available data for pathological complete response, EFS, and OS; and have a median follow-up of at least 3 years. We compared the three most commonly used definitions of pathological complete response--ypT0 ypN0, ypT0/is ypN0, and ypT0/is--for their association with EFS and OS in a responder analysis. We assessed the association between pathological complete response and EFS and OS in various subgroups. Finally, we did a trial-level analysis to assess whether pathological complete response could be used as a surrogate endpoint for EFS or OS. FINDINGS: We obtained data from 12 identified international trials and 11 955 patients were included in our responder analysis. Eradication of tumour from both breast and lymph nodes (ypT0 ypN0 or ypT0/is ypN0) was better associated with improved EFS (ypT0 ypN0: hazard ratio [HR] 0·44, 95% CI 0·39-0·51; ypT0/is ypN0: 0·48, 0·43-0·54) and OS (0·36, 0·30-0·44; 0·36, 0·31-0·42) than was tumour eradication from the breast alone (ypT0/is; EFS: HR 0·60, 95% CI 0·55-0·66; OS 0·51, 0·45-0·58). We used the ypT0/is ypN0 definition for all subsequent analyses. The association between pathological complete response and long-term outcomes was strongest in patients with triple-negative breast cancer (EFS: HR 0·24, 95% CI 0·18-0·33; OS: 0·16, 0·11-0·25) and in those with HER2-positive, hormone-receptor-negative tumours who received trastuzumab (EFS: 0·15, 0·09-0·27; OS: 0·08, 0·03, 0·22). In the trial-level analysis, we recorded little association between increases in frequency of pathological complete response and EFS (R(2)=0·03, 95% CI 0·00-0·25) and OS (R(2)=0·24, 0·00-0·70). INTERPRETATION: Patients who attain pathological complete response defined as ypT0 ypN0 or ypT0/is ypN0 have improved survival. The prognostic value is greatest in aggressive tumour subtypes. Our pooled analysis could not validate pathological complete response as a surrogate endpoint for improved EFS and OS. FUNDING: US Food and Drug Administration.

Trastuzumab emtansine for HER2-positive advanced breast cancer.

BACKGROUND: Trastuzumab emtansine (T-DM1) is an antibody-drug conjugate incorporating the human epidermal growth factor receptor 2 (HER2)-targeted antitumor properties of trastuzumab with the cytotoxic activity of the microtubule-inhibitory agent DM1. The antibody and the cytotoxic agent are conjugated by means of a stable linker. METHODS: We randomly assigned patients with HER2-positive advanced breast cancer, who had previously been treated with trastuzumab and a taxane, to T-DM1 or lapatinib plus capecitabine. The primary end points were progression-free survival (as assessed by independent review), overall survival, and safety. Secondary end points included progression-free survival (investigator-assessed), the objective response rate, and the time to symptom progression. Two interim analyses of overall survival were conducted. RESULTS: Among 991 randomly assigned patients, median progression-free survival as assessed by independent review was 9.6 months with T-DM1 versus 6.4 months with lapatinib plus capecitabine (hazard ratio for progression or death from any cause, 0.65; 95% confidence interval [CI], 0.55 to 0.77; P<0.001), and median overall survival at the second interim analysis crossed the stopping boundary for efficacy (30.9 months vs. 25.1 months; hazard ratio for death from any cause, 0.68; 95% CI, 0.55 to 0.85; P<0.001). The objective response rate was higher with T-DM1 (43.6%, vs. 30.8% with lapatinib plus capecitabine; P<0.001); results for all additional secondary end points favored T-DM1. Rates of grade 3 or 4 adverse events were higher with lapatinib plus capecitabine than with T-DM1 (57% vs. 41%). The incidences of thrombocytopenia and increased serum aminotransferase levels were higher with T-DM1, whereas the incidences of diarrhea, nausea, vomiting, and palmar-plantar erythrodysesthesia were higher with lapatinib plus capecitabine. CONCLUSIONS: T-DM1 significantly prolonged progression-free and overall survival with less toxicity than lapatinib plus capecitabine in patients with HER2-positive advanced breast cancer previously treated with trastuzumab and a taxane. (Funded by F. Hoffmann-La Roche/Genentech; EMILIA ClinicalTrials.gov number, NCT00829166.).

The immune system and response to HER2-targeted treatment in breast cancer.

The monoclonal antibody trastuzumab targets the growth factor receptor HER2 and has profoundly improved the course of disease and survival of women with HER2-overexpressing breast cancer. Because trastuzumab targets aberrant expression of HER2 in tumours addicted to HER2 activation, its clinical activity is credited largely to inhibition of intracellular signalling. A growing body of preclinical and clinical evidence shows that the immune system contributes substantially to the therapeutic effects of trastuzumab and other monoclonal antibodies in vivo. Furthermore, findings indicate that immune-related markers can provide useful predictive information and that increased clinical activity might follow activation of the immune system. Development of immunomodulatory drugs with remarkable activity in many solid tumours defines a scenario in which the combination of immune modulation with trastuzumab, or other HER2-directed drugs, will result in augmented response and clinical outcome.

Neoadjuvant and adjuvant trastuzumab in patients with HER2-positive locally advanced breast cancer (NOAH): follow-up of a randomised controlled superiority trial with a parallel HER2-negative cohort.

BACKGROUND: In our randomised, controlled, phase 3 trial NeOAdjuvant Herceptin (NOAH) trial in women with HER2-positive locally advanced or inflammatory breast cancer, neoadjuvant trastuzumab significantly improved pathological complete response rate and event-free survival. We report updated results from our primary analysis to establish the long-term benefit of trastuzumab-containing neoadjuvant therapy. METHODS: We did this multicentre, open-label, randomised trial in women with HER2-positive locally advanced or inflammatory breast cancer. Participants were randomly assigned (1:1), by computer program with a minimisation technique, to receive neoadjuvant chemotherapy alone or with 1 year of trastuzumab (concurrently with neoadjuvant chemotherapy and continued after surgery). A parallel group with HER2-negative disease was included and received neoadjuvant chemotherapy alone. Our primary endpoint was event-free survival. Analysis was by intention to treat. This study is registered at www.controlled-trials.com, ISRCTN86043495. FINDINGS: Between June 20, 2002, and Dec 12, 2005, we enrolled 235 patients with HER2-positive disease, of whom 118 received chemotherapy alone and 117 received chemotherapy plus trastuzumab. 99 additional patients with HER2-negative disease were included in the parallel cohort. After a median follow-up of 5.4 years (IQR 3.1-6.8) the event-free-survival benefit from the addition of trastuzumab to chemotherapy was maintained in patients with HER2-positive disease. 5 year event-free survival was 58% (95% CI 48-66) in patients in the trastuzumab group and 43% (34-52) in those in the chemotherapy group; the unadjusted hazard ratio (HR) for event-free survival between the two randomised HER2-positive treatment groups was 0.64 (95% CI 0.44-0.93; two-sided log-rank p=0.016). Event-free survival was strongly associated with pathological complete remission in patients given trastuzumab. Of the 68 patients with a pathological complete response (45 with trastuzumab and 23 with chemotherapy alone), the HR for event-free survival between those with and without trastuzumab was 0.29 (95% CI 0.11-0.78). During follow-up only four cardiovascular adverse events were regarded by the investigator to be drug-related (grade 2 lymphostasis and grade 2 lymphoedema, each in one patient in the trastuzumab group, and grade 2 thrombosis and grade 2 deep vein thrombosis, each in one patient in the chemotherapy-alone group). INTERPRETATION: These results show a sustained benefit in event-free survival from trastuzumab-containing neoadjuvant therapy followed by adjuvant trastuzumab in patients with locally advanced or inflammatory breast cancer, and provide new insight into the association between pathological complete remission and long-term outcomes in HER2-positive disease.

Everolimus for women with trastuzumab-resistant, HER2-positive, advanced breast cancer (BOLERO-3): a randomised, double-blind, placebo-controlled phase 3 trial.

BACKGROUND: Disease progression in patients with HER2-positive breast cancer receiving trastuzumab might be associated with activation of the PI3K/Akt/mTOR intracellular signalling pathway. We aimed to assess whether the addition of the mTOR inhibitor everolimus to trastuzumab might restore sensitivity to trastuzumab. METHODS: In this randomised, double-blind, placebo-controlled, phase 3 trial, we recruited women with HER2-positive, trastuzumab-resistant, advanced breast carcinoma who had previously received taxane therapy. Eligible patients were randomly assigned (1:1) using a central patient screening and randomisation system to daily everolimus (5 mg/day) plus weekly trastuzumab (2 mg/kg) and vinorelbine (25 mg/m(2)) or to placebo plus trastuzumab plus vinorelbine, in 3-week cycles, stratified by previous lapatinib use. The primary endpoint was progression-free survival (PFS) by local assessment in the intention-to-treat population. We report the final analysis for PFS; overall survival follow-up is still in progress. This trial is registered with ClinicalTrials.gov, number NCT01007942. FINDINGS: Between Oct 26, 2009, and May 23, 2012, 569 patients were randomly assigned to everolimus (n=284) or placebo (n=285). Median follow-up at the time of analysis was 20.2 months (IQR 15.0-27.1). Median PFS was 7.00 months (95% CI 6.74-8.18) with everolimus and 5.78 months (5.49-6.90) with placebo (hazard ratio 0.78 [95% CI 0.65-0.95]; p=0.0067). The most common grade 3-4 adverse events were neutropenia (204 [73%] of 280 patients in the everolimus group vs 175 [62%] of 282 patients in the placebo group), leucopenia (106 [38%] vs 82 [29%]), anaemia (53 [19%] vs 17 [6%]), febrile neutropenia (44 [16%] vs ten [4%]), stomatitis (37 [13%] vs four [1%]), and fatigue (34 [12%] vs 11 [4%]). Serious adverse events were reported in 117 (42%) patients in the everolimus group and 55 (20%) in the placebo group; two on-treatment deaths due to adverse events occurred in each group. INTERPRETATION: The addition of everolimus to trastuzumab plus vinorelbine significantly prolongs PFS in patients with trastuzumab-resistant and taxane-pretreated, HER2-positive, advanced breast cancer. The clinical benefit should be considered in the context of the adverse event profile in this population.

Relationship between HER2 expression and efficacy with first-line trastuzumab emtansine compared with trastuzumab plus docetaxel in TDM4450g: a randomized phase II study of patients with previously untreated HER2-positive metastatic breast cancer.

INTRODUCTION: The purpose of this study was to retrospectively explore the relationship between human epidermal growth factor receptor 2 (HER2) messenger RNA (mRNA) expression and efficacy in patients receiving trastuzumab plus docetaxel (HT) or trastuzumab emtansine (T-DM1). METHODS: Patients with HER2-positive, locally advanced or metastatic breast cancer (MBC) were randomly assigned to HT (n=70) or T-DM1 (n=67). HER2 status was assessed locally using immunohistochemistry or fluorescence in situ hybridization and confirmed retrospectively by central testing. HER2 mRNA expression was assessed using quantitative reverse transcriptase polymerase chain reaction. RESULTS: HER2 mRNA levels were obtained for 116/137 patients (HT=61; T-DM1=55). Median pretreatment HER2 mRNA was 8.9. The risk of disease progression in the overall population was lower with T-DM1 than with HT (hazard ratio (HR)=0.59; 95% confidence interval (CI) 0.36 to 0.97). This effect was more pronounced in patients with HER2 mRNA≥median (HR=0.39; 95% CI 0.18 to 0.85) versus

2 years versus 1 year of adjuvant trastuzumab for HER2-positive breast cancer (HERA): an open-label, randomised controlled trial.

BACKGROUND: Trastuzumab has established efficacy against breast cancer with overexpression or amplification of the HER2 oncogene. The standard of care is 1 year of adjuvant trastuzumab, but the optimum duration of treatment is unknown. We compared 2 years of treatment with trastuzumab with 1 year of treatment, and updated the comparison of 1 year of trastuzumab versus observation at a median follow-up of 8 years, for patients enrolled in the HERceptin Adjuvant (HERA) trial. METHODS: The HERA trial is an international, multicentre, randomised, open-label, phase 3 trial comparing treatment with trastuzumab for 1 and 2 years with observation after standard neoadjuvant chemotherapy, adjuvant chemotherapy, or both in 5102 patients with HER2-positive early breast cancer. The primary endpoint was disease-free survival. The comparison of 2 years versus 1 year of trastuzumab treatment involved a landmark analysis of 3105 patients who were disease-free 12 months after randomisation to one of the trastuzumab groups, and was planned after observing at least 725 disease-free survival events. The updated intention-to-treat comparison of 1 year trastuzumab treatment versus observation alone in 3399 patients at a median follow-up of 8 years (range 0-10) is also reported. This study is registered with ClinicalTrials.gov, number NCT00045032. FINDINGS: We recorded 367 events of disease-free survival in 1552 patients in the 1 year group and 367 events in 1553 patients in the 2 year group (hazard ratio [HR] 0·99, 95% CI 0·85-1·14, p=0·86). Grade 3-4 adverse events and decreases in left ventricular ejection fraction during treatment were reported more frequently in the 2 year treatment group than in the 1 year group (342 [20·4%] vs 275 [16·3%] grade 3-4 adverse events, and 120 [7·2%] vs 69 [4·1%] decreases in left ventricular ejection fraction, respectively). HRs for a comparison of 1 year of trastuzumab treatment versus observation were 0·76 (95% CI 0·67-0·86, p<0·0001) for disease-free survival and 0·76 (0·65-0·88, p=0·0005) for overall survival, despite crossover of 884 (52%) patients from the observation group to trastuzumab therapy. INTERPRETATION: 2 years of adjuvant trastuzumab is not more effective than is 1 year of treatment for patients with HER2-positive early breast cancer. 1 year of treatment provides a significant disease-free and overall survival benefit compared with observation and remains the standard of care. FUNDING: F Hoffmann-La Roche (Roche).

Phase I clinical and pharmacokinetic study of ombrabulin (AVE8062) combined with cisplatin/docetaxel or carboplatin/paclitaxel in patients with advanced solid tumors.

PURPOSE: Preclinical evidence supports synergy between the vascular disrupting agent ombrabulin and various chemotherapy agents. Ombrabulin was combined with two standard taxane/platinum doublets in a phase I study to determine the recommended combination doses. METHODS: Ombrabulin (30-min infusion, day 1 every 3 weeks) was escalated from 15.5 to 35 mg/m(2) with two chemotherapy doublets; OCD, 75 mg/m(2) cisplatin (C), day 1 (cohort 1) or day 2 (cohort 2) with 60/75 mg/m(2) docetaxel (D), day 2; and OCP, AUC5/6 carboplatin (C) and paclitaxel (P) 175 mg/m(2) (cohort 3) or 200 mg/m(2) (cohort 4), day 2. Safety, pharmacokinetics, and tumor response were evaluated. RESULTS: Sixty-nine patients were treated (32 OCD, 37 OCP). Four had DLTs in cycle 1, two in cohort 1 (grade 4 febrile neutropenia, grade 4 pulmonary embolism) and one each in cohorts 2 (grade 3 ALT elevation) and 4 (grade 3 peripheral ischemia). Ombrabulin escalation in cohorts 2, 3 and 4 was halted at the highest planned dose (35 mg/m(2)). Asthenia, nausea, paresthesia, alopecia, vomiting, and stomatitis were common, as was grade 3-4 neutropenia. Ombrabulin clearance was high with a short terminal half-life and a medium volume of distribution. Pharmacokinetic analysis showed no clinically relevant drug interactions between the taxane-platinum doublet and ombrabulin or its active metabolite RPR258063, however docetaxel and carboplatin pharmacokinetics were slightly altered. One complete and 15 partial responses (10 OCD, 5 OCP; median duration 5.5 and 4.4 months, respectively) were reported. CONCLUSIONS: The addition of ombrabulin to standard doses of cisplatin/docetaxel or carboplatin/paclitaxel proved feasible with manageable overlapping toxicities but appears to have limited impact on the efficacy of these doublets. Recommended combination doses are 35 mg/m(2) ombrabulin with 75 mg/m(2) cisplatin/75 mg/m(2) docetaxel or 200 mg/m(2) paclitaxel/AUC6 carboplatin, every 3 weeks.